local logger = require "logger";
local lxp = require "lxp"
local init_xmlhandlers = require "core.xmlhandlers"
local sm_new_session = require "core.sessionmanager".new_session;
local s2s_new_incoming = require "core.s2smanager".new_incoming;
local s2s_streamopened = require "core.s2smanager".streamopened;
local s2s_streamclosed = require "core.s2smanager".streamopened;
local s2s_destroy_session = require "core.s2smanager".destroy_session;

local stream_callbacks = { streamopened = s2s_streamopened, streamclosed = s2s_streamclosed };

local connlisteners_register = require "net.connlisteners".register;

local t_insert = table.insert;
local t_concat = table.concat;
local t_concatall = function (t, sep) local tt = {}; for _, s in ipairs(t) do t_insert(tt, tostring(s)); end return t_concat(tt, sep); end
local m_random = math.random;
local format = string.format;
local sm_new_session, sm_destroy_session = sessionmanager.new_session, sessionmanager.destroy_session; --import("core.sessionmanager", "new_session", "destroy_session");
local st = stanza;

local sessions = {};
local xmppserver = { default_port = 5269 };

-- These are session methods --

local function session_reset_stream(session)
	-- Reset stream
		local parser = lxp.new(init_xmlhandlers(session, stream_callbacks), "|");
		session.parser = parser;
		
		session.notopen = true;
		
		function session.data(conn, data)
			parser:parse(data);
		end
		return true;
end


local stream_xmlns_attr = {xmlns='urn:ietf:params:xml:ns:xmpp-streams'};
local function session_disconnect(session, reason)
	local log = session.log or log;
	if session.conn then
		if reason then
			if type(reason) == "string" then -- assume stream error
				log("info", "Disconnecting %s[%s], <stream:error> is: %s", session.host or "(unknown host)", session.type, reason);
				session.sends2s(st.stanza("stream:error"):tag(reason, {xmlns = 'urn:ietf:params:xml:ns:xmpp-streams' }));
			elseif type(reason) == "table" then
				if reason.condition then
					local stanza = st.stanza("stream:error"):tag(reason.condition, stream_xmlns_attr):up();
					if reason.text then
						stanza:tag("text", stream_xmlns_attr):text(reason.text):up();
					end
					if reason.extra then
						stanza:add_child(reason.extra);
					end
					log("info", "Disconnecting %s[%s], <stream:error> is: %s", session.host or "(unknown host)", session.type, tostring(stanza));
					session.sends2s(stanza);
				elseif reason.name then -- a stanza
					log("info", "Disconnecting %s->%s[%s], <stream:error> is: %s", session.from_host or "(unknown host)", session.to_host or "(unknown host)", session.type, tostring(reason));
					session.sends2s(reason);
				end
			end
		end
		session.sends2s("</stream:stream>");
		session.conn.close();
		xmppserver.disconnect(session.conn, "stream error");
	end
end


-- End of session methods --

function xmppserver.listener(conn, data)
	local session = sessions[conn];
	if not session then
		session = s2s_new_incoming(conn);
		sessions[conn] = session;

		-- Logging functions --

		local mainlog, log = log;
		do
			local conn_name = "s2sin"..tostring(conn):match("[a-f0-9]+$");
			log = logger.init(conn_name);
		end
		local print = function (...) log("info", t_concatall({...}, "\t")); end
		session.log = log;

		print("Incoming s2s connection");
		
		session.reset_stream = session_reset_stream;
		session.disconnect = session_disconnect;
		
		session_reset_stream(session); -- Initialise, ready for use
		
		-- FIXME: Below function should be session,stanza - and xmlhandlers should use :method() notation to call,
		-- this will avoid the useless indirection we have atm
		-- (I'm on a mission, no time to fix now)

		-- Debug version --
		local function handleerr(err) print("Traceback:", err, debug.traceback()); end
		session.stanza_dispatch = function (stanza) return select(2, xpcall(function () return core_process_stanza(session, stanza); end, handleerr));  end
	end
	if data then
		session.data(conn, data);
	end
end
	
function xmppserver.disconnect(conn)
	local session = sessions[conn];
	if session then
		s2s_destroy_session(session);
		sessions[conn]  = nil;
		session = nil;
		collectgarbage("collect");
	end
end

function xmppserver.register_outgoing(conn, session)
	session.direction = "outgoing";
	sessions[conn] = session;
	
	session.reset_stream = session_reset_stream;	
	session_reset_stream(session); -- Initialise, ready for use
	
	-- FIXME: Below function should be session,stanza - and xmlhandlers should use :method() notation to call,
	-- this will avoid the useless indirection we have atm
	-- (I'm on a mission, no time to fix now)
	session.stanza_dispatch = function (stanza) return core_process_stanza(session, stanza); end
end

connlisteners_register("xmppserver", xmppserver);


-- We need to perform some initialisation when a connection is created
-- We also need to perform that same initialisation at other points (SASL, TLS, ...)

-- ...and we need to handle data
-- ...and record all sessions associated with connections